the warming of the Earth by the atmosphere because of water vapor and gases such ascarbon dioxide, which absorb and emitinfrared radiation, or heat. Thus, thehigh-energy photons such as light andultraviolet radiationare passed through the atmosphere to the Earth, which tends to absorb them andemit lower-energy photons which are then captured in the atmosphere and partially sentback to Earth. As the presence of infrared absorbers rises in the atmosphere, the moresolar energy is retained at heat in the atmosphere and on the surface of the Earth.Because glass also passes light and tends to absorb and reflect heat, this effect iscompared to that of a greenhouse.